Fix double comparisons for Media Queries

third_party/WebKit/Source/core/css/MediaQueryEvaluator.cpp

Index: third_party/WebKit/Source/core/css/MediaQueryEvaluator.cpp
diff --git a/third_party/WebKit/Source/core/css/MediaQueryEvaluator.cpp b/third_party/WebKit/Source/core/css/MediaQueryEvaluator.cpp
index 92f06db9a7cd19e5f68faa2f22a832b5fd6ecfd7..02bbd5f9ae29ae40b45776932f98fc8f329a3c8b 100644
--- a/third_party/WebKit/Source/core/css/MediaQueryEvaluator.cpp
+++ b/third_party/WebKit/Source/core/css/MediaQueryEvaluator.cpp
@@ -173,6 +173,20 @@ bool compareValue(T a, T b, MediaFeaturePrefix op)
     return false;
 }
 
+bool compareDoubleValue(double a, double b, MediaFeaturePrefix op)
+{
+    const double precision = 0.000001;

[rune, 2016/04/20 07:04:46]

We use std::numeric_limits<T>::epsilon() other places. Would that be an
appropriate constant to use here?

[Yoav Weiss, 2016/04/20 07:26:57]

yup

+    switch (op) {
+    case MinPrefix:
+        return a >= (b - precision);
+    case MaxPrefix:
+        return a <= (b + precision);
+    case NoPrefix:
+        return abs(a - b) <= precision;
+    }
+    return false;
+}
+
 static bool compareAspectRatioValue(const MediaQueryExpValue& value, int width, int height, MediaFeaturePrefix op)
 {
     if (value.isRatio)
@@ -374,7 +388,7 @@ static bool computeLength(const MediaQueryExpValue& value, const MediaValues& me
 static bool computeLengthAndCompare(const MediaQueryExpValue& value, MediaFeaturePrefix op, const MediaValues& mediaValues, double compareToValue)
 {
     double length;
-    return computeLength(value, mediaValues, length) && compareValue(compareToValue, length, op);
+    return computeLength(value, mediaValues, length) && compareDoubleValue(compareToValue, length, op);
 }
 
 static bool deviceHeightMediaFeatureEval(const MediaQueryExpValue& value, MediaFeaturePrefix op, const MediaValues& mediaValues)